Automatic negative pressure drainage device based on steeply inclined short-distance coal seam horizontal sublevel mining

The invention provides an automatic negative pressure drainage device based on steeply-inclined short-distance coal seam horizontal sublevel mining, and belongs to the field of coal seam mining. The automatic negative pressure drainage device comprises a shell, a support is fixedly arranged at the bottom of the shell, a drainage assembly is arranged in the shell, a water inlet pipe is arranged at the top of the shell in a penetrating mode, and a valve is installed on the water inlet pipe; a drainage pipe is arranged at the bottom end of one side of the shell in a penetrating mode, and self-closing valve assemblies are arranged at the inner ends of the water inlet pipe and the drainage pipe; and the cleaning assembly comprises a partition plate, a filter screen, a collecting box, a scraping plate, a first sealing plug and a threaded cylinder. The self-closing valve assembly and the water drainage assembly are arranged, automatic water drainage operation can be achieved, the structure is simple, efficiency is h